vacum port/80 gs750

[Anonymous]

allright, just got new carbs off ebay and rebuilt them with all new internals
(floats,jets,gaskets,etc.) i then put the carbs on it and hooked up the gas hose, and tryed to start it,nothing happens, no coughing or sputtering just motor turning over. all i hooked up was the gas hose and not the vacum port. unscrewed the bowl drain screws and no gas came out, so i went to take the tank off and when i took the hose off the carb. gas started coming out of the bowl drain screws. so evidently i have vapor lock, so i look at the petcock and there is another place to put a hose but it was filled w/gasket sealent, so i cleaned it out and gas started coming from it(is that normal?). so my question is will the bike start without the vacum port connected to the carbs or at least sputter?

http://www.thegsresources.com/images/carbs/004_Vacuum%20Port%20to%20Petcock.jpg

i would have stopped right there and gone and got some hose but my throttle cable broke when i was trying to start it, also the reason i bought
new carbs is because i had vm29 aftermarket carbs that came with the bike when i bought it and i could never get them tuned to the motor(wrong cutouts on the throttle vavle?)

here is a link to a picture of my bike, please help!

http://www.chopperunderground.com/forums/index.php?act=ST&f=14&t=5804&s=4d81b033ee1c0f9668a302ae05559c70

[Anonymous]

There should be no gas in the vacum port on the pet cock. Bike should start with open vacum port on the #2 carb, but the #2 cylinder won't run right with that vacum leak. Sounds like your 29 mm carbs didn't have a vacum port, so the vacum port on the pet cock was pluged, then pet cock set to the pri position so fuel would flow without vacum.

[Anonymous]

petcock

thanks for the reply, rphillips
after i wrote post, i went outside and looked at petcock and it was still leaking from the vacum side(gas all over lift ) it is a stedy flow of gas
(not dribble) coming out of the vacum side. so i'm going to replace petcock. (leaking means its bad, right?)
i was reading post found by "search" feature and everbody seems to think pingel is the best?! what i don't like is that u have to cut the pingel to make it fit right? does anybody know where i could find a petcock that doesn't need to be cut to fit? thanks for all the help!

[luc8421]

before you buy a new petcock, I would suggest rebuilding the original, the vacum diaphram is most likely faulty.

http://www.crc2onlinecatalog.com/Index_Main_Frame.htm

I'm not sure what bike you have, but the above sites has $20 rebuild kits for most suzuki bikes, including a new diaphram.

[SqDancerLynn1]

If someone has been messing with the petcock DOn't try to rebuild it GET a new one. GO down towards the bottom of the page there are some vacuum OEM type replacements

http://www.cyclewareables.com/pages/street_motorcycle_petcock_oem_and_custom_units/fuelpetcock.htm